Microelectromechanical systems (MEMS) devices generally have a high mechanical Q (e.g., 50 to 100) and device position is usually a non-linear function of applied voltage, especially in the case of gap-closing actuators. This behavior makes actuation and control of MEMS devices challenging. The transient device performance and control schemes for optimizing device characteristics such as settling time are critical in many applications and are not often reported. Schemes for closed-loop control of MEMS devices using proportional-integral-differential (PID) controllers or adaptive controllers have been proposed. Such schemes may alleviate the above difficulties but require position sensors and often complex circuitry. Open-loop control schemes using various filters and pulse-shaping are simpler to implement for many applications. However, such schemes may not be able to operate at low voltages.
It is within this context that embodiments of the present invention arise.